#print(i)
IntNode.append([node,node.get_node_id()])
IntNode_ID=sorted(IntNode, key = itemgetter(1))
IntNode_Ordered=[node[0] for node in IntNode_ID]
#print(IntNode_Ordered,IntNode_Ordered[0].get_node_id()._id_no)
#
#
#
for j, node in enumerate(IntNode_Ordered):
boundary_sum=[]
id1=node.get_node_id()
coord=node.get_coord()
for endpt in (connect_iterator(grid, id1)):
if grid.get_slave(endpt):
connect_value=grid.get_matrix_value(id1, endpt)
#print(node.get_node_id()._id_no,endpt._id_no)
boundary_sum.append(true_soln(grid.get_coord(endpt))*connect_value)
load_vector[j]=load_vector[j]-sum(boundary_sum)
#print(load_vector)
#
for i in range(len(IntNode_Ordered)):
load_value=IntNode_Ordered[i].get_load()
#print(load_value)
load_vector[i]= load_vector[i]+load_value
#
# Enumerate interior NodeID in order of ID
NodeID_Load=[]
# Which row corresponds to the current node?
i = int(node.get_value())
# Add in the entry to the load vector
coord = node.get_coord()
load_vector[i] = load_vector[i] + rhs(coord)
# Loop over the matrix entries in the current row
for endpt1 in connect_iterator(grid, node.get_node_id()):
# Which column corresponds to the current node?
j = int(grid.get_value(endpt1))
# What is the corresponding matrix value (in the FEM grid)
stiffness = grid.get_matrix_value(node.get_node_id(), endpt1)[0]
# We must not include slave nodes in the matrix columns
if not grid.get_slave(endpt1):
fem_matrix[i, j] = stiffness
# Update the load vector to take non-zero boundary conditions
# into account
else:
coord = grid.get_coord(endpt1)
load_vector[i] = load_vector[i] - stiffness * true_soln(coord)
# Solve the system Ax = b
value_vector = linalg.solve(fem_matrix, load_vector)
# Initialise a vector to keep track of the errors
#print(q)
NodeID_Load.append(node.get_node_id())
NodeID_Load.sort()
# For every NodeID in NodeID_load, find its connecting nodes, reorder them and assign them in stiffness matrix
for i, nodeid in enumerate(NodeID_Load):
Endpt=[]
for j, endpt1 in enumerate(connect_iterator(grid, nodeid)):
Endpt.append(endpt1)
Endpt.sort()
#B=[]
for k,endpt2 in enumerate(Endpt):
#B.append([k,endpt2])
stiffness = grid.get_matrix_value(nodeid,endpt2)
fem_matrix[i,k]=stiffness*float(64)
#print(i,k,nodeid._id_no,endpt2._id_no,stiffness)
#print(nodeid._id_no,endpt2._id_no,stiffness)
##############################################################
#print(fem_matrix)
#############################################################
#Solve for the apprxoimating nodal value and find the true value at those nodes
value_vector = linalg.solve(fem_matrix , load_vector)
true_vector=[]
for i in range(len(IntNode_Ordered)):
true_vector.append(true_soln(IntNode_Ordered[i].get_coord()))